A physical network can be divided into a plurality of virtual networks by using a network slicing technology. A virtual network is considered as a “network slice”. Network slices are independent of each other. Network function customization and management are performed for each network slice based on a requirement of a service scenario. A terminal device has a plurality of sessions, and different sessions may require network slices corresponding to the sessions to provide services. In this case, if the terminal device needs to access a network and set up a plurality of sessions, a base station connected to the terminal device needs to support a network slice corresponding to all or some of the sessions of the terminal device.
In this case, how to improve a handover success probability is a problem worth considering.